The objective of this study was to investigate the influence of type of cross-linking method used on the properties of ambroxol hydrochloride microspheres such as encapsulation efficiency, particle size, and drug release. Microspheres were prepared by solvent evaporation technique using chitosan as a matrix-forming agent and cross-linked using formaldehyde and heat treatment. Morphological and physicochemical properties of microspheres were then investigated by scanning electron microscopy (SEM), X-ray diffractometry (XRD), differential scanning calorimetry (DSC), and Fourier-transform infrared spectroscopy (FTIR) spectroscopy. The cross-linking of chitosan takes place at the free amino group because of formation of imine bond as evidenced by FTIR. The DSC, XRD, and FTIR analysis showed that chitosan microspheres cross linked by heating were superior in properties and performance as compared to the microspheres cross-linked using formaldehyde. SEM results revealed that heat-treated microspheres were spherical, discrete having smooth, and porous structure. The particle size and encapsulation efficiencies of the prepared chitosan microspheres ranged between 10.83–24.11 μm and 39.73μ80.56%, respectively. The drug release was extended up to 12 h, and the kinetics of the drug release was obeying Higuchi kinetic proving diffusion-controlled drug release.

This work was done for the investigations of anti-inflammatory and analgesic activities of methanolic extract of dried leaves of Ficus benghalensis Linn. by oral administration at doses of 10, 20 and 100 mg/kg of body weight to healthy animals. The extract was studied for anti-inflammatory activity by using carrageenan-induced hind paw edema in rats. The mean increases in paw volume and % inhibition in the edema were measured plethysmometrically at different time intervals after carrageenan (1% w/v) injection. The extract was also evaluated for analgesic activity using acetic acid-induced writhing and Eddy's hot plate method in albino mice. The methanolic extract of F. benghalensis showed significant (P<0.05) reduction in carrageenan-induced paw edema and analgesic activity evidenced from decreased acetic acid-induced writhings and increased reaction time in Eddy's hot plate method. Results of present studies suggest that methanolic extract of F. benghalensis possesses significant (P<0.05) anti-inflammatory and analgesic activities.

Background:Oral sustained release gastroretentive dosage forms offer many advantages for drugs having absorption from upper gastrointestinal tract and improve the bioavailability of medications that are characterized by narrow absorption window. The aim of current study was to design sustained release bioadhesive gastroretentive dosage form of ofloxacin.Materials and Methods:A 32 full factorial design was employed to systematically study the drug release profile and bioadhesive strength. Carbopol 934P and HPMC K100M were selected as the independent variables. Compatibility between drug and polymer was tested by fourier transform infrared (FTIR) and X-ray diffraction (XRD) techniques. Tablets were prepared by direct compression and were evaluated for tablet characteristics, swelling study, adhesion strength, percent drug released, radiographic imaging study and stability study. The optimized formulation was then compared with marketed formulation (Oflin OD®).Results:Tablets prepared showed good tablet characteristics, optimum swelling property, and good adhesion strength with high detachment force. Most of the formulations including the optimized formulation followed Higuchi kinetics and the drug release mechanism was found to be anomalous. Radiographic image proved that tablet remains intact in its structural integrity and shape in stomach up to 24 h. The short-term accelerated stability testing was carried out for the optimized formulation, and results revealed that drug content, in-vitro dissolution and all other parameters were within acceptable limits.Conclusion:Thus, the prepared bioadhesive gastroretentive ofloxacin tablet may prove to be a potential candidate which increases the bioavailability of ofloxacin for any intragastric condition.

Background:The main aim of this study was to develop a gastroretentive, multiple-unit floating drug delivery system for a drug which is poorly absorbed from the lower gastrointestinal tract. Such a dosage form may provide an extended retention of drug in the upper gastrointestinal tract resulting in enhanced absorption and improved bioavailability.Materials and Methods:Microspheres were prepared by the emulsion solvent diffusion method. Four different ratios (1:1, 1:2, 1:3, and 1:4) from each polymer, i.e., Eudragit RL 100 (E1–E4) and cellulose acetate (C1–C4) were prepared.Results:Hollow microspheres were characterized by particle size using optical microscopy. The in vitro release data obtained for the formulations E1–E4 and C1–C4 showed good entrapment efficiency, good percentage buoyancy, and prolonged drug release. The in vitro drug release showed the highest regression coefficient values for Higuchi's model, indicating diffusion to be the predominant mechanism of drug release. The surface and cross-sectional morphology of the formulations E1-A and C1-A were determined using scanning electron microscopy.Conclusions:Thus, prepared floating hollow microspheres of famotidine may prove to be potential candidates for the multiple-unit drug delivery device adaptable for any intragastric condition.

The drug delivery system is most important and preferable drug delivery system. This route has high patient acceptability, primarily due to easy of administration. Effective oral drug delivery depends upon the factors such as gastric emptying process, the gastrointestinal transit time of the dosage form drug release from the dosage form, and site of absorption of drug. In recent years, scientific and technological advancements have been made in the research and development of gastro retentive drug delivery systems. Hence forth a wide spectrum of dosage forms has been developed for the drugs which have narrow absorption window, unstable at intestinal pH, are soluble in acidic pH, and have a site of action specific to stomach. The purpose of writing this review was to investigate, compile and present the recent as well as past literature in a more concise way with a special focus on approaches that are currently utilized in the prolongation of gastric residence time. These include floating system, swelling and expanding system, bio/mucoadhesive system, high-density system, and other delayed gastric emptying devices. The present review addresses briefly the classification, formulation consideration for Gastroretantive drug delivery system (GRDDS), factors controlling gastric retention, merits, demerits, and applications of gastro retentive drug delivery systems.